The rate of type 2 diabetes has been increasing in recent years, and health researchers expect it to be one of the most important public health challenges in the near future. Type 2 diabetes usually develops in adulthood and in some cases can be resolved (taken into remission) with appropriate lifestyle changes. Many patients with Type 2 diabetes are also obese, and for those patients, weight loss is an important factor in improving their condition or completely curing it.
Although weight loss surgery has also been increasing rapidly, until recently the effects of weight loss surgery on diabetes haven’t been studied systematically. A group of Australian researchers, led by John Dixon, Ph.D., decided to study directly the effect of adjustable gastric banding (lap band) on diabetes with a clinical trial that compared the results of patients treated with conventional life-style therapy alone to those who received conventional therapy plus lap banding. The results of this study were reported in the Journal of the American Medical Association in 2008.
The Conventional Approach vs. Lap Banding
Patients in the study who were in the control group were given the conventional treatments most doctors use with obese, diabetic patients: diabetes medications; diet recommendations that included calorie reduction, low glycemic index, high fiber, and low fat; and recommendations to exercise regularly. Patients in the surgical group got all of that, plus the placement of a gastric band to limit the effective size of the stomach.
Lap Band Surgery Greatly Increases Chances of Remission of Diabetes
The results are striking: after two years, 73% of the patients who had the lap band surgery had achieved remission of their diabetes and no longer needed to take diabetes medication. Only 13% of those in the conventional-therapy group had the same success.
Patients in the group that received surgery had also lost more weight: the average weight loss in the surgical group was 20.7% of body weight, while the conventional-therapy group lost an average of only 1.7% of body weight. Patients in the surgical group were also able to reduce or eliminate their use of medications for high blood pressure at significantly higher rates than patients in the control group.
It’s How Much You Lose That Matters, Not How You Lose It
An important finding of this study was that the improvement in blood sugar levels and the achievement of remission of type 2 diabetes was closely correlated with the amount of weight lost. The authors of the study say that no patients in the study were able to achieve remission without losing at least 10% of their body weight.
The bottom line is that for extremely obese patients, losing at least 10% of body weight is necessary to make significant improvement with diabetes. Patients who had the lap band procedure were far more likely to lose significant amounts of weight.
Dr Dixon and his colleagues note that one implication of their study is that conventional therapy for weight loss might need to be more intensive in order to have greater chance of success. As attention continues to focus on weight loss and diabetes therapy, perhaps new intensive weight-loss therapy programs will be developed. But for patients considering gastric banding as a way to lose weight and address diabetes, lap banding might currently be the best option.